PEG模拟干旱胁迫对不同糜子品种萌发的影响

Effects of PEG simulated drought stress on the germination of different Panicum miliaceum L.varieties

【目的】探究干旱胁迫对不同糜子品种的萌发影响,明确糜子萌发期的抗旱评价指标及不同品种的抗旱能力。【方法】以育成审(认)定且糜子主产区种植面积较大的20个糜子品种为试验材料,利用20%的PEG-6000溶液模拟干旱胁迫,测定发芽势、发芽率、胚芽长、胚芽鞘长、侧根数、胚根长、萌发指数和发芽指数8个萌发性状,用相关性分析和隶属函数分析进行糜子萌发期抗旱性评价。【结果】干旱胁迫下,20个糜子品种发芽势、发芽率、胚芽长、胚芽鞘长、侧根数、胚根长、萌发指数和发芽指数均受到抑制,其中,陇糜15号发芽势、发芽率、萌发指数和发芽指数受到的抑制最强,降低率分别为59.05%、43.05%、68.68%、65.99%;陇糜7号受到抑制较轻,降低率分别为20.41%、11.49%、40.51%、36.78%。隶属函数值综合评价结果表明,陇糜7号抗旱能力较强,为0.868,陇糜15号抗旱能力较弱,为0.093。相关性分析表明,相对萌发指数、相对发芽势、相对胚芽长、相对胚芽鞘长、相对胚根长、相对侧根数与隶属函数综合评价值(D值)显著相关。【结论】筛选出了抗旱能力较强的品种陇糜7号和抗旱能力较弱品种陇糜15号;相对萌发指数、相对发芽势、相对胚芽长、相对胚芽鞘长、相对胚根长、相对侧根数可作为糜子萌发期抗旱评价的参考指标。

【Objective】Explore the effect of drought stress on the germination of different Panicum miliaceum L.varieties,to clarify the drought resistance evaluation index of Panicum miliaceum L.during germination stage and the drought resistance ability of different varieties.【Methods】Twenty registered Panicum miliaceum L.varieties with large planting areas in the main producing areas were used as experimental materials.20%PEG-6000 solution was used to simulate drought stress.Eight germination traits including germination potential,germination rate,embryo length,coleoptile length,lateral root number,radicle length,germination index and sprout index were measured.The drought resistance of Panicum miliaceum L.at germination stage was evaluated by correlation analysis and membership function analysis.【Results】Under drought stress,the germination potential,germination rate,embryo length,coleoptile length,lateral root number,radicle length,germination index and sprout index of the 20 Panicum miliaceum L.varieties were all inhibited.Among them,the germination potential,germination rate,germination index and sprout index of Longmei No.15 were inhibited most,with reduction rates of 59.05%,43.05%,68.68%,and 65.99%,respectively.Longmei No.7 were less inhibited,with reduction rates of 20.41%,11.49%,40.51%,and 36.78%,respectively.The membership function value comprehensive evaluation results showed that the drought resistance ability of Longmei No.7 was stronger at 0.868,while Longmei No.15 was weaker at 0.093.Correlation analysis showed that,relative germination index,relative germination potential,relative embryo length,relative coleoptile length,relative radicle length,and relative lateral root number were significantly correlated with the membership function comprehensive evaluation value(D value).【Conclusion】Longmei No.7 was screened as strong drought resistance variety while Longmei No.15 was the weak drought resistance variety.Relative germination index,relative germination potential,relative embryo length,relative coleoptile length,relative radicle length and relative lateral root number can be used as reference indexes for drought resistance evaluation of Panicum miliaceum L.at germination stage.